The following background information may present examples of specific aspects of the prior art (e.g., without limitation, approaches, facts, or common wisdom) that, while expected to be helpful to further educate the reader as to additional aspects of the prior art, is not to be construed as limiting the present invention, or any embodiments thereof, to anything stated or implied therein or inferred thereupon.
The following is an example of a specific aspect in the prior art that, while expected to be helpful to further educate the reader as to additional aspects of the prior art, is not to be construed as limiting the present invention, or any embodiments thereof, to anything stated or implied therein or inferred thereupon.
The present invention is directed to an elevator that traverses a double ladder in a smooth continuous path. The elevator uses specially oriented and aligned rollers and wheels to engage the side rails. The rollers and wheels can selectively engage either ladder, or the overlap portion between the ladders, depending on the position of the elevator on the double ladder.
It is well known that ladders have been commonly used in order to carry a person or worker up or down along a building wall or other structure. Ladders can include a rigid pair of side rails connected by horizontal rungs. Sometimes, two or more ladders can be joined to extend the potential height of the ladder.
It can sometimes be problematic to carry heavy objects to the top of a house, to a second or higher story of a building, or onto a roof. For example, carrying heavy materials like shingles up a ladder with hands is a dangerous proposition in that carrying such materials may require the use of both hands. Furthermore, manually carrying multiple packages of shingles, tools, or perhaps beverages is likely to require multiple trips up and down the ladder, which creates a more dangerous climbing scenario.
Often, the lifting can be accomplished with a crane, but the expense of using a crane is often prohibitive. The manpower to operate the crane might not be available. In addition, it would be difficult and expensive to transport a large piece of equipment such as a crane to a job site.
Often, a specially configured elevator is used to automatically climb the ladder. The elevator is a motorized platform that rides the side rails of the ladder to move up and down the ladder. However, if the ladder is a double or triple ladder having more than one individual sections, the junction between the ladders is generally wider and less stable than at the single ladder sections. The elevator may not be able to cross these junctions where the ladders overlap.
For the foregoing reasons, there is an elevator that traverses a double ladder in a smooth, continuous path through the use of strategically placed guides and rollers that engage specific surfaces and flanges on the double ladder.
Elevators for ladders have been utilized in the past; yet none with the present double ladder climbing capacity of the present invention. See U.S. Pat. Nos. 2,499,975; 3,215,254; and 6,782,972.
For the foregoing reasons, there is a double ladder elevator that traverses double ladders in a first position, a second position, and an overlap position.